Multiplexing Apparatus, Multiplexing Method, Program, and Recording Medium

1. A multiplexing apparatus for multiplexing audio data into transport stream (TS) packets, the multiplexing apparatus comprising: first encoding means for encoding the audio data by a first encoding method, which is a predetermined encoding method; second encoding means for encoding the audio data by a second encoding method, which is a variable-length encoding method, which differs from the first encoding method, and which attaches a timing value indicating a timing used when audio data is decoded in units of predetermined audio data; packetization means for packetizing the audio data encoded by the first encoding means and the audio data encoded by the second encoding means into TS packets and for attaching the same ID to a plurality of packetized TS packets; determination means for determining a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization means; and multiplexing means for multiplexing the TS packet determined by the determination means, wherein the determination means assumes a first system target decoder for decoding the audio data encoded by the first encoding means and a second system target decoder for decoding the audio data encoded by the second encoding means on the basis of the timing value attached to the audio data encoded by the second encoding means, and determines a TS packet to be multiplexed, wherein the determination means determines a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization means on the basis of a first elementary buffer possessed by the first system target decoder and a rate at which data is transferred to the first elementary buffer and on the basis of a second elementary buffer possessed by the second system target decoder and a rate at which data is transferred to the second elementary buffer.

2. The multiplexing apparatus according to claim 1 , wherein the determination means determines a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization means so that the first elementary buffer possessed by the first system target decoder and the second elementary buffer possessed by the second system target decoder do not overflow or underflow.

3. The multiplexing apparatus according to claim 1 , further comprising recording means for recording the TS packets multiplexed by the multiplexing means on a recording medium.

4. The multiplexing apparatus according to claim 1 , wherein the unit of the audio data is an audio access unit.

5. The multiplexing apparatus according to claim 1 , wherein the first system target decoder has a transport buffer at a stage prior to the first elementary buffer, and the second system target decoder has a transport buffer at a stage prior to the second elementary buffer and has a third elementary buffer at a stage subsequent to the second elementary.

6. The multiplexing apparatus according to claim 5 , wherein the determination means determines a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization means by assuming that the timing for input to the third elementary buffer is a timing for the timing value.

7. The multiplexing apparatus according to claim 6 , wherein the timing value is a value represented by a sampling period of audio information, at which the unit of an audio stream is passed to the third elementary buffer.

8. A multiplexing method for use with a multiplexing apparatus for multiplexing audio data into transport stream (TS) packets, the multiplexing method comprising the steps of: encoding the audio data by a first encoding method, which is a predetermined encoding method; encoding the audio data by a second encoding method, which is a variable-length encoding method, which differs from the first encoding method, and which attaches a timing value indicating a timing used when audio data is decoded in units of predetermined audio data; packetizing the audio data encoded in the first encoding step and the audio data encoded in the second encoding step into TS packets and attaching the same ID to a plurality of packetized TS packets; determining a TS packet to be multiplexed from among the plurality of TS packets packetized in the packetization step; and multiplexing the TS packet determined in the determination step, wherein the determination step assumes a first system target decoder for decoding the audio data encoded in the first encoding step, and a second system target decoder for decoding the audio data encoded in the second encoding step on the basis of the timing value attached to the audio data encoded in the second encoding step, and determines a TS packet to be multiplexed, wherein the determining step determines a TS packet to be multiplexed from among the plurality of TS packets packetized in the packetizing step on the basis of a first elementary buffer possessed by the first system target decoder and a rate at which data is transferred to the first elementary buffer and on the basis of a second elementary buffer possessed by the second system target decoder and a rate at which data is transferred to the second elementary buffer.

9. A computer readable medium having recorded thereon a program with computer readable instructions that when executed multiplex audio data into transport stream (TS) packets, the instructions when executed by processor perform processing comprising the steps of: encoding with the processor the audio data by a first encoding method, which is a predetermined encoding method; encoding the audio data by a second encoding method, which is a variable-length encoding method, which differs from the first encoding method, and which attaches a timing value indicating a timing used when audio data is decoded in units of predetermined audio data; packetizing the audio data encoded in the first encoding step and the audio data encoded in the second encoding step into TS packets and attaching the same ID to a plurality of packetized TS packets; determining a TS packet to be multiplexed from among the plurality of TS packets packetized in the packetization step; and multiplexing the TS packet determined in the determination step, wherein the determination step assumes a first system target decoder for decoding the audio data encoded in the first encoding step, and a second system target decoder for decoding the audio data encoded in the second encoding step on the basis of the timing value attached to the audio data encoded in the second encoding step, and determines a TS packet to be multiplexed, wherein the determining step determines a TS packet to be multiplexed from among the plurality of TS packets packetized in the packetizing step on the basis of a first elementary buffer possessed by the first system target decoder and a rate at which data is transferred to the first elementary buffer and on the basis of a second elementary buffer possessed by the second system target decoder and a rate at which data is transferred to the second elementary buffer.

10. A multiplexing apparatus for multiplexing audio data into transport stream (TS) packets, the multiplexing apparatus comprising: a first encoding section encoding the audio data by a first encoding method, which is a predetermined encoding method; a second encoding section encoding the audio data by a second encoding method, which is a variable-length encoding method and which differs from the first encoding method, for attaching a timing value indicating a timing used when audio data is decoded in units of predetermined audio data; a packetization section packetizing the audio data encoded by the first encoding section and the audio data encoded by the second encoding section into TS packets and attaching the same ID to a plurality of packetized TS packets; a determination section determining a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization section; and a multiplexing section multiplexing the TS packet determined by the determination section, wherein the determination section assumes a first system target decoder for decoding the audio data encoded by the first encoding section and a second system target decoder for decoding the audio data encoded by the second encoding section on the basis of the timing value attached to the audio data encoded by the second encoding section, and determines a TS packet to be multiplexed, wherein the determination section determines a TS packet to be multiplexed from among the plurality of TS packets packetized by the packetization section on the basis of a first elementary buffer possessed by the first system target decoder and a rate at which data is transferred to the first elementary buffer and on the basis of a second elementary buffer possessed by the second system target decoder and a rate at which data is transferred to the second elementary buffer.